MA Test Adapters for Condenser Microphones of the fet 80601 page 1of 13 1) General 2} What can be measured? 3) What aids and instruments are necessary? 4) Which MA is required for which microphone? §) How should measurements be made? 5.1 Voltage gain 5.2 Output capability 8.
MA Test Adapters for Condenser Microphones of the fet 80601 page General The MA test adapters are used to replace the capsule head of microphones during measurements on the amplifier. They prevent acoustic interference which could be channeled through the capsule and yet have the capsule's impedance so that the amplifier can operate under its normal operating conditions. 2) M What can be measured? 2.1 Supply voltage and current consumption, nominal voltages in the amplifier Z.
MA Test Adapters for Condenser Microphones of the fet 80601 page Voltage meter for unweighted and weighted measurements in accordance with CIR 468-1 (1976) or IEC 268-1 (flat RMS, weighted peak or weighted RMS) 3.6 Static or compensation voltmeter for measuring the polarization voltage of the capsule; depending on the microphone type V 3.7 Linear test amplifier as the sensitivity of normal meters is insufficient for measuring the Tow self noise levels (depending on microphone type 1...
MA Test Adapters for Condenser Microphones of the fet 80601 page 4 of 13 Test Adapters 4.1 KM B3i/KM B4 /KM 851: The MA 84 test adapter consists of one part, has one measuring input and is screwed onto the microphone instead of the capsule. 4.2 KMS B4 i/KMS 851 MA 84, as described in 4.1, With these microphones, the grille must first be unscrewed and, in the case of the KMS 841, this is done by turning the wire gauze part to the left.
MA Test Adapters for Condenser Microphones of the fet 80601 page 5of 13 The insulating foil which protects the capsule against electrical shorts to the inner tube wall remains in the tube.
MA Test Adapters for Condenser Microphones of the fet 80601 page 861/KM 86: The MA 861 or MA 86 test adapter consists of two parts and comprises a replacement capsule head with its input socket and a housing tube which accommodates the amplifier to be tested. The amplifier may be pulled out downwards after turning the three screws on the bottom of the housing inwards (clockwise) and can be inserted into the tube of the test adapter.
MA Test Adapters for Condenser Microphones of the fet 80601 page 7 of 13 The unscrewed capsule must not be turned with respect to the capsule housing.
MA Test Adapters for Condenser Microphones of the fet 80601 page 8of 13 The U 871 may be dismantled after unscrewing the Target bottom ring with nameplate, by turning it to the Tet. The conical housing tube may then be = removed. The capsule grille and also the test adapter are held to the amplifier body by two spring~loaded levers which may be depressed and pushed inwards with the thumb and index finger. Test socket assignments: black: zero potential; red: to the capsule base-point. 4.
MA Test Adapters for Condenser Microphones of the fet ’ 80601 page of 13 In order to measure the self-noise voltage, this microphone must be inserted into the sound-proof EK 89 et MPR microphone testing tube as it is not possible / in this case to simulate the capsule by means of a fixed capacitance (refer to 5.3). 4.
MA Test Adapters for Condenser Microphones of the fet 80601 page 100of 13 switching of the voltage at the test input to amplifier I {yellow) or 1I (red) and is provided with the corresponding markings. 4.11 QM 69: The MAQ test adapter consists of one part, has a switchable test input and is placed onto the amplifier instead of the capsule. For this purpose, the three Philips screws on the bottom edge of capsule head must be unscrewed.
MA Test Adapters for Condenser Microphones of the fet 80501 page 11 013 test microphone power supply adapter amplifier unit generator AF voltmeter ac power line The measurement can be repeated at severs) frequencies to check the frequency response of the amplifier, It is usually sufficient to carry out measurements kHz, and 16 kHz. 5.
MA Test Adapters for Condenser Microphones of the fet 80®~ Series 80601 page Self-noise level Definition: The self-noise level of a microphone is the noise level measured at the output when no sound is directed towards the microphone and when there is no external noise field. The unweighted noise level is measured via a filter with a linear attenuation between 31.